Continuous supply edge-to-edge laminate for plastic cards and method of fabrication

ABSTRACT

A laminate of transparent flexible material is formed to the precise size of a substrate and is made so that it will be laminated in place on the substrate. The laminate is in an elongated web that is separated into individual laminate sections by transverse lines of reduced tear strength so that the laminate sections can be removed from the web sequentially.

CROSS REFERENCE TO RELATED APPLICATION

[0001] Reference is made to U.S. patent application Ser. No. ______,filed on even date herewith and entitled “WASTELESS LAMINATOR”(Attorney's Docket F12.12-0051) and assigned to the same assignee asthis application.

BACKGROUND OF THE INVENTION

[0002] This invention relates to a web or continuous strip of clearlaminate that is formed to the exact size of a substrate on which thelaminate is to be used, and which web has reduced strength linestransversely of the web at the exact or very slightly shorter lengthdimension of the substrate on which it is to be applied.

[0003] Plastic cards used for identification cards are personalized withtext and images using resin and dye diffusion thermal transfer (D2T2)ribbons. Unless protected with another resin layer or film laminate, thedye (and thus the image printed) can rapidly degrade from abrasion,chemical attack from plasticizers such as those found in vinyl walletwindows, and from ultraviolet radiation (UV), for example.

[0004] Thermal transfer resin layers typically used in the plastic cardindustry consist of thin acrylic coatings. These provide some protectionto the card surface and printed information, however, but longer termdurability is a problem, as none of these thermal transfer materials isdurable enough to satisfy customers. A second problem is that dyemigration may still occur since the thermal film is made of porousmaterial which cannot protect the dye from plasticizers and the like.

[0005] A third problem is in the application of the material as it tendsnot to stay on the card when laminated, especially along the edges ofthe card, and it flakes when laminated causing debris problems in theprinter.

[0006] In order to improve on these thin thermal transfer layers,thicker laminates consisting of polyester film (PET) coated with athermal transfer adhesive have been developed. In one type of laminatesystem, these laminate “chips” or “patches” are placed adhesive-side upon a pressure sensitive adhesive (PSA) coated carrier film of PET.During lamination to the card in the printer, the patch is transferredto the surface of the card. These types of patches typically cover onlyabout 90% of the card surface. Dye migration, UV fading and abrasion canstill occur on the edges of the card. Laminate patches can also be cutfrom a supply roll of PET film laminate and applied to cards in theprinter, however, these rectangular patches also only cover about 90% ofthe card.

[0007] The use of individual laminate patches carried on a backing filmfor lamination onto a substrate is shown in U.S. Pat. Nos. 5,807,461 and4,617,080. Also, the application of an overlay film on a printed paperis disclosed in U.S. Pat. Nos. 4,522,881; 4,599,259; and 4,977,136. Theuse of a continuous web with weakened transverse lines for separationsections is not shown.

SUMMARY OF THE INVENTION

[0008] The present invention relates to providing a transparent laminatematerial and scoring transverse lines on the web to form individualsections of a size that fits edge to edge on the length and width of asubstrate. The transverse lines are weakened to have a tear strength inthe range of two pounds tensile pull for standard two inch widths. Thisstrength is obtainable for commonly used laminate thickness of 1.0 to1.5 mils. The tear strength is selected to permit separating out theindividual sections for laminating them to a substrate, a range of tearstrength from about 0.75 pounds per inch of width to about 1.25 poundsper inch with the three pound maximum will work. The sizes can becontrolled to within a few thousandths of an inch so the laminatesections which are nominally full size or very close to full size of thesubstrate, can be laminated on substrates without waste and usingautomated equipment. Virtually the entire card surface will be covered.Present automated equipment requires no more than 3 lb. tensile pull forsevering individual sections.

[0009] The full size lamination section or patch protects the substrate,such as an identification card so the full surface of the substrate canbe used for printing or otherwise recording information.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010]FIG. 1 is a plan view of a section of a web of laminate havingindividual sections formed to conform to a substrate comprising anidentification card;

[0011]FIG. 2 is a schematic representation of one form of separatingindividual sections on the web;

[0012]FIG. 3 is a modified method of separating individual sections onthe web;

[0013]FIG. 4 is a plan view of a substrate having a lamination sectionlaminated thereon;

[0014]FIG. 5 is a side view of FIG. 4; and

[0015]FIG. 6 is a block diagram representing the steps of utilization ofthe individual sections of a web shown in FIG. 1.

DETAILED DESCRIPTION OF THE ILLUSTRATIVE EMBODIMENTS

[0016] Referring to FIG. 1, a supply spool indicated generally at 12 isused to provide a continuous web 13 of a transparent material that canbe laminated onto a suitable substrates, such as that shown at 15 (FIG.5). The material preferably is a polyester film with a thermal transferadhesive on one surface. The continuous web 13 is divided intoindividual sections 16, which are of size to fit the substrate 15, whichis shown as an identification card. Individual sections 16 are formed byscore lines or lines of weakened material indicated generally at 18 thatextend transversely of the web. In addition, the corners 20 of theindividual sections are rounded to conform to the shape of the substrate15. The web is fed to a suitable machine, for separation along theweakened lines 18, and then handled in a manner that will index it tothe individual substrates 15 and apply it as a laminate edge-to-edge,end-to-end, and around the corner configurations of the substrates. Thesections 16 have a thermal transfer adhesive layer 17 on one surface,for adhering the laminate section to the substrate 15.

[0017] The rounded corners that are formed to fit the card corners, andthe transverse weakened lines that delineate the individual laminatesections can be made by laser cutting. The transverse weakened lines areeither formed by reducing the thickness of material when the web ismade, by perforating the web material, or by die cutting slits acrossthe web material. The smooth edges needed can be obtained by all threeforms, but die cutting or laser cutting, which both permit cutting therounded corners at the same time as the transverse weakened lines areexemplary.

[0018]FIG. 2 illustrates a weakened line 18A that is microperforationsthat can be made by various methods, such as an exemplary form using diecuts. The perforations are very small, so that the edge is essentiallycontinuous, clean and straight when it is separated off from the web.

[0019]FIG. 2 shows a modified form that can be used by die cut wherethere is a cut shown at 18B between individual sections 16 that is ofreduced thickness, so that there is a weakened transverse line acrossthe web that can permit the individual sections to be severed, forexample by holding one of the sections (usually at the supply roll end)and snapping the other one with a clamp member.

[0020] The lines of weakened material are designed to have a breakstrength that will permit snapping the sections from the web easily. Abreak strength of about two-thirds of the holding force applied to theend section will work. For example, a break strength of 2 pounds for atwo inch wide web has been found satisfactory for existing equipment. Amaximum break strength is about 3 pounds for a two-inch wide web sincethe weakened line has to break at tension loads well below the web breakstrength. Also the breaking is done with automated equipment that applythe tension loads, and the equipment has maximum load limits forreliable breaking. The weakened lines also have to be strong enough towithstand the tension when the roll is unwound and pulled to a positionwhere it can be broken. Thus, the web weakened line should preferablyhave a separation strength of not less than 0.75 pounds per inch ofwidth, but have a maximum break strength less than a preferred 1 poundper inch of width. The severed or broken edges are smoother with lowerbreak strengths.

[0021] Various other ways of forming the transverse reduced strength orweakened line can be used. It is essential, however, that the edge ofthe laminate is not frayed or irregular, but is very smooth so that whenit is laminated to a substrate 15, such as an identification card, itcan come out all to within 0.10 mils from the edge to completely covervirtually all of the information on the card.

[0022] The edges must appear smooth to the eye or people will tend totry to lift the edges. Also the edges must feel smooth to the touch oragain the natural tendency is to rub the edge of the card and to try tolift the laminate. Additionally, the rounded corners 20 can be cut in asuitable manner such as with dye cutting, water jet, or with lasercutting. This type of laminate, that goes edge-to-edge and end-to-end onthe substrate 15 can include holographic images or optical variabledevices and can cover films (either clear or with DVDs or holographs) aswell as regular printed materials.

[0023]FIG. 6 is a flow diagram indicating the use of the transparentindividual sections 16. The first step indicated at block 30 is toweaken the continuous web along transverse lines (called score lines)and cut the corners to size. The web of transparent material is thusdivided into individual laminate sections, and is rewound onto a supplyroll.

[0024] The weakened lines will be formed to provide the desired tear orbreak strength, as shown at block 31.

[0025] Then as shown at block 32 the individual laminate sections areseparated for individually laminating the sections onto a card. This canbe done by any desired mechanism, but generally it would be by applyinga holding force to the web, usually on the next to the end section onthe web, and then applying a pulling force (tension) to the end sectionand moving that to a location. Reference is made to application Ser. No.______ for WASTELESS LAMINATOR (Attorney's Docket F12.12-0051)identified above.

[0026] Block 32 represents separating the individual laminate sectionsof a selected size from the web, and then block 34 is for indexing thesections to be in registry with a substrate or card. At block 36laminating the individual transparent laminate section in the properposition on the substrate completes the lamination process. The laminatesection of transparent material can be a few thousands of an inch (say0.010 inch) smaller than the substrate, so the edges of the laminate donot snag in use.

[0027] It has been found that clear 1.3 mil polyester material makes agood laminating material. Material sold under the mark TRANSGUARD byTransilwrap Company of Franklin Park, Ill. is satisfactory. The originalcontinuous web is processed to separate the individual sections by thetransverse lines of reduced strength, formed by laser cutting or die cutperforation. Holographic laminate material also can be used. Suchmaterial is made by Crown Roll Leaf and Holipak Industries, both of NewJersey. Also, for reverse image printing a vinyl chloride-vinyl acetatecoated film can be used. The corners can be cut with laser cuts, to makethem perfectly smooth, and the transverse line of reduced strength canbe made so that the desired tension load will cause the individualsections to separate. The approximately two pounds of tension forseparating sections of a two-inch wide web mentioned above has beenfound to be satisfactory, since the force that is available forseparating the sections and driving the web with existing equipment islimited to approximately 3 lbs.

[0028] The laminate material for forming the laminate sections does nothave to be clear, but can be opaque for some uses. The section can beformed to a precise size and laminated on top of each other to form amulti-layer card, such as the 3M Secure® Card. The section can beseparated and fed with automated equipment after severing them from theweb for lamination of a plurality of layers to form such a card. Eachlaminate section is applied to an underlying layer. That is essentiallya substrate.

[0029] Although the present invention has been described with referenceto preferred embodiments, workers skilled in the art will recognize thatchanges may be made in form and detail without departing from the spiritand scope of the invention.

What is claimed is:
 1. A laminate section defined in a web of thelaminate material, said laminate section being formed to the outerperipheral size of an underlying layer on which the laminate section isto be placed, and a transverse line of reduced strength across the webto define the individual section from the rest of the web.
 2. Thelaminate section of claim 1, wherein the laminate material is apolyester film.
 3. A laminate section for a laminating to an underlyinglayer of material having a length, width and corner configurationdefined by edges, said laminate section being trimmed to conform to thelength, width and corner configuration of the underlying layer on whichit is to be laminated, such that the laminate section extends to alignwith outer edges of the underlying layer.
 4. The laminate of claim 3,wherein the laminate is a transparent material.
 5. The laminate of claim4, wherein the laminate material is coated with a thermal transferadhesive.
 6. The laminate of claim 4, wherein the laminate material ispolyester film.
 7. The laminate of claim 4, wherein the laminatematerial is a polyester film having properties of material sold underthe trademark TRANSGUARD by Transilwrap Company, Inc.
 8. The laminate ofclaim 4, wherein the underlying layer is a card and the laminatematerial is a Holographic material.
 9. A laminate web of at least twolaminate sections for a substrate having a length, width and cornerconfiguration, said laminate web having a transverse weakened strengthmark, said transverse weakened strength mark having a separation loadper inch of not less than 0.75 pound and preferably not greater than 1pound.
 10. The laminate of claim 10, wherein the separation load is lessthan a maximum of 3 pounds of tensile loading per inch of width.
 11. Thelaminate of claim 10, wherein the laminate is a transparent material.12. The laminate of claim 10, wherein the laminate is a Holographicmaterial.
 13. The laminate of claim 10, wherein the laminate is made ofone material selected from the group consisting of polyester film, avinyl chloride-vinylacitate coated film, and Holographic film.
 14. Thelaminate of claim 9 and a coating of a thermal transfer adhesive on onesurface of the laminate.